Railway switch operating apparatus



May 27,1941; L, BONE 2,243,727

RAILWAY SWITCH OPERATING APPARATUS Filed June 22, 1939 3 Sheets-Sheet 1HIS ATTORNEY y 27, 1941. H. L. BONE 2,242,727

- RAILWAY SWITCH OPERATING APPARATUS Filed June 22, 1939 3 Sheets-Sheet2 HIS ATTORNEY May 2-7, 1941. O 4 2,243,727

RAILWAY SWITCH OPERATING APPARATUS Filed June 22, 1939 3 Sheets-Sheet 3Patented May 27, 1941 UNITED STATES PATENT OFFICE RAILWAY SWITCHOPERATING APPARATUS Herbert L. Bone, Forest Hills, Pa, assignor to TheUnion Switch & Signal Company, Swissvale, Pa., a corporation ofPennsylvania Application J une 22, 1939,'S erial No. 280,600

4 Claims.

My invention relates to railway switch operating apparatus, andparticularly to' apparatus of the type which includes a facing pointlock the locking plunger of which is automatically operated to unlocl;the switch when a train trailsthe switch by means mechanically actuatedby the train.

One object of my invention is to provide, in apparatus of the typedescribed, an electrically operated means for positively preventingoperation of the locking plunger for any reason, as for example, bydragging equipment, during facing point moves over the switch.

Other objects and characteristic features of my invention will becomeapparent as the description proceeds.

My present invention is an improvement on the apparatus described andclaimed in Letters Patent of the United States No. 1,976,827, granted tome on October 16, 1934, for Railway switch operating apparatus.

I shall describe one form of apparatus embodying my invention, and shallthen point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a top plan view showing a springswitch A controlled by a switch operating mechanism B constructed inaccordance with my invention. Fig. 2 is an enlarged top plan View of theswitch operating mechanism B shown in Fig. 1 with the circuit controllerand the'main cover removed to better illustrate the novel portion of themechanism. Fig. 3 is a longitudinal sectional View of the mechanismshown in Fig. 2. Fig. 4 is a detail sectional view taken substantiallyon the line IV-IV of Fig. 3. Fig. 5 is a detail view of electric lockmechanism forming part of the switch operating mechanism illustrated inthe preceding views, and embodying my present invention.

Similar reference characters refer to similar parts in each of theseveral views.

Referring first to Fig. 1, the reference character A designates'arailway switch comprising, as usual, two fixed rails l and la and twomovable rails 2 and 2a. The fixed rails l and la are laid on tie plates3 and are secured to cross ties 4 in the usual manner. The movable rails2 and 2a are fastened together by a front rod 5, a head rod 6, a bridlerod '1, and a tie rod 8, and may be moved into a normal or a reverseposition by means of a switch operating mechanism B which is connectedwith the head rod 6 through the medium of an operating rod 9 anda springconnecting rod C. When the switch occupiesits normal position in whichposition it is shown in'Fig. 1, the movable rail 2 engages the fixedrail l', and the movable rail 2a is spaced a slight distanc'e'from thefixed rail I a. When the switch is reversed, however, the movable rail2a then engages the fixed rail la and the movable rail 2 is spaced fromthe fixed rail I.

The spring connecting rod C may have any desired construction, but ashere illustrated,'it is similar in all respects to that described in myprior'patent referred to hereinb'efo-re. It is believ'ed, therefore,that for purposes of my present invention itis sufficient topoin'toutthat this connecting rod includes spring means which biases the switchpoints to whichever extreme position they are moved to by the mechanismB with sufficient force to permit facing point moves over the-switchwithout displacement of the points, but which yields when a train trailsthe switch and thereby allows the train to force the switch points to aposition opposite to that to which they are biased by the spring means.

The switch operating mechanism B is mounted on one end of a tie strapI!) which is secured to the tiesadjacent the outer side of the rail I,and, asbest seen in Figs. 2 and 3, this mechanism, in the-form hereshown, comprises a main casing H provided at its left-hand end with atail-like projection Ila to which an auxiliary casing housing, a circuitcontroller E (see Fig. 1) is secured. The upper end of the main casing His closed by a cover I2 which is secured to the casing by means'of studsl2a, as shown in Fig. 3.

The circuit controller E forms no part of my present invention and may,for example, be similar to the circuit controller E shown and describedin my prior patent referred to hereinbefore. Inasmuch as this circuitcontroller forms no part of my present invention, it is believed to beunnecessary to describe it further herein.

Formed in the main casing H is an axially extending rectangular guidewayl3 which slidably receives a motion plate Hi. The motion plate I4 isprovided on its upper face with rack teeth [5-, and on its lower .facewith a cam slot of movement of the motion plate. Extending into the camslot l6 and cooperating therewith is a roller 2| which is mounted on apin 22 secured to an arm 23 forming part of a crank 24. The crank 24 isjournaled in a vertical bearing 25 provided in the bottom of the 'casingH and has fixed thereto on the underside of the casing a removableswitch operating arm 26 which is pivotally attached to the free end ofthe operating rod 9.

Reciprocably mounted in the casing l directly above the motion plate [4is a locking. device 21' comprising two spaced parallel side members 21aand 21b connected together attheir opposite ends by means of integralend members 210 and 21d. The left-hand end member 21c carries arectangular locking plunger 21e, and is formed with two spaced threadedholes 21) and 21g, while'the other end member 21d is provided withthreeunthreaded holes 21h, 219' and 2110, two of which holes, 21h and21k align, respectively, with the threaded holes 21f and 21g. Thelocking plunger 21c projects with some clearance into alongitudinallyextending rectangular slot 28 provided in the tail-likeprojection I la of the casing II, and cooperates at its inner end with alock rod L which is slidably mounted in a transverse slot 29 formed inthe tail-like projection I la. The lock rod L, in the form here shown,is of standard construction, and comprises two longitudinally adjustablebars 30 and 3| attached at one end to the front rod of the switch A, andprovided with registering notches 32 so disposed that these notches willalign with the locking plunger 21s when and only when the switch Aoccupies the extreme position in which it is shown in Fig. 1. Thelocking device 21 also comprises two bolt members 211 and 21m which passthrough the holes 21h and 21k, respectively, and are screwed into thethreaded holes 21 and. 21g. These bolt members also extend with someclearance through holes 33 and 34 formed in lugs 35 and 36 secured tothe upper face of the motion plate I4, and surrounding each bolt memberbetween the associated lug 35 or 36 and the end member 21d is acompressed coil spring 21n which biases the locking device 21 in thedirection to cause the locking plunger 21e to enter the notches 32 inthe lock rod L.

Vertical displacement of the locking device 21 and the motion plate Mare prevented by a holddown member 40 (see Fig. 4) which hold-downmember is formed integrally with a casting 4| which is bolted at one endto the opposite sides of the casing H by means of bolts 42, and. at theother end to the casing by means of the previously referred to studs|2a. The hold-down member 40 is provided on its underside near itsopposite ends with hold-down surfaces 40a and 4012 which .are adapted toslidably engage the upper edges of the side members 21a and 21b,respectively, of

the locking device 21.

For reasons which are clearly explained in my prior patent referred tohereinbefore, the

with some clearance through the hole 217' in the end member 2111, andthe head of which bolt engages the left-hand side of the end member 21:!as viewed in Figs. 2 and 3. The threaded end of plunger bolt 50 isadjustably connected by means of a turnbuckle 5 (see Fig. 1) with oneend of a link 52, the opposite end of which is pivotally connected withthe long arm 53a of a bell crank lever 53. The bell crank lever 53 ispivotally supported in a crank stand 54, and has its short arm 53bpivot-ally connected with one end of an operating rod 55. The other endof the operating rod 55 is connected with the previously described tierod 6 by means of a standard switch basket 56. The tie rod 8' may belocated at any suitable location, but will preferably be locatedapproximately halfway between the heel and the point of the switch. Thebase of the crank stand 54 is secured both to a gauge plate 51 and tothe tie strap I0 upon which the mechanism B is mounted, and it will beapparent, therefore, that any loss of adjustment between the parts dueto creepage of the ties is prevented. The plunger bolt 50, turnbuckle5|, link 52, bell crank lever 53, operating rod 55, spring basket 56,and tie rod 8 also constitute means for efiecting unlocking of theswitch points during a trailing move, as will be made clear presently.

'The operation, as a whole, of the portion of the apparatus thus fardescribed is as follows: When the hand-throw lever l1 occupies theextreme position in which it is shown in full lines in Figs. 1 and 2,the motion plate I4 is held in its extreme left-hand or normal positionas viewed in Figs. 2 and 3, and the roller 2| on crank 24 is held at theextreme end of its stroke in a clockwise direction, as viewed in Figs. 1and 2. When the crank 24 occupies this extreme position, a force isexerted on the movable rails 2 and 2a of the switch through the mediumof the operating rod 9, the spring connecting rod C, and the head rod 6,which force holds the movable rails in their normal extreme positions inwhich they are shown in Fig. 1. When the movable rails are in theirnormal positions, the notches 32 in the lock rod L align with thelocking plunger 21e, and the locking device 21 is therefore moved by thebiasing springs 21n to its locking position in which the locking plungerpartly enters the registering notches 32, thus securely locking theswitch points in their normal positions.

When it is desired to reverse the switch, the

hand-throw lever I1 is rotated from the extreme plate l4 to move fromits extreme left-hand position as viewed in Figs. 2 and 3, to itsextreme right-hand position. As soon as the motion plate has moved ashort distance, the lugs 35 and 36 carried thereby engage the left-handside of the end member 21d of the locking device 21, and as a result, asthe motion plate continues to'move, the locking device is moved with themotion plate, thus Withdrawing the locking plunger from engagement withthe notches 32 in the lock rod L, and hence unlocking the movable rails2 and 2a. The parts are so proportioned that while the locking plunger21e is being withdrawn from engagement with the notches 32 in the lockrod, the cam slot I6 in the motion plate will continue to engage theroller 2| on the crank 24 at that portion of the slot at its right-handend which is parallel to the direction of movement ofthe motion plate,and as long as this portion of the slot is. engaging the roller, thecrank 24 will remain stationary. It follows, therefore, that during thatportion of the movement of the motion plate which is necessary to unlockthe movable rails of the switch, no force is exerted on these railstending to reverse them. As-soon, however, as this first part of themovement of the motion plate has been completed, the roller 2! is thenengaged by the curved portion of the cam slot l5 which causes the crank24 to be rotated in a counterclockwise direction, as viewed in. Fig. 2,and as a result, the movable rails are then moved to their reversepositions.

It should be noted that as long as themovable rails remain stationary,the plunger bolt remains fixed, so that during the first part of themovement of the motion plate, the end member 21d of the locking device21 will move out of engagement with the head of 'the plunger bolt. Assoon as the movable rails have started to move, however, the resultantmovement of the tie rod 8 acting through the switch basket 56, operatingrod 55,. bell crank lever 53, and link 52 causes the plunger bolt tomove in the same tion of the crank 24, thus locking the movable rails intheir reverse positions.

In order to restore the movable rails totheir normal positions afterthey have been reversed as above described, the lever ll is restored tothe position in which it is shown in fulllines in the drawings. Thesubsequent movements of the parts under these conditions are just thereverse of those described above, and it is believed, therefore, thatthe operation of the apparatus under these conditions will be readilyunderstood from an inspection of the drawings without furtherdescription.

I shall now assume that the parts are in their normal positions, asshown in the drawings, and that a train trails the switch. .As theleading wheels of the train roll along the fixed rail 1 and the movablerail 2a, the movable rails. 2 and 2a are forced over laterally, but,before a sufficient force isdeveloped to overcome the opposing force ofthe spring of the spring connecting rod C and cause the point of themovable rail 2 to move out of engagement with the fixed rail I, themovable rails being somewhat resilient become bent, so that, with theusual standard split switch, the tie rod 8 is moved upwardly, as viewedin Fig. 1, three-quarters of an inch or more. This movement of the tierod acting through the switch basket 55, operating rod 55, bell cranklever 53, link 52, and plunger bolt 50 moves the locking device 27 inopposition to the bias of the springs 2m 2. sufiicient amount towithdraw the locking plunger 21c completely out of engagement with thenotches 32 in the'lock rod L, thus unlocking the switch. As a result,when the leading wheels have reached the positions in which a sufficientforce is developed to cause the point of the movable rail 2 to move outof engagement with the fixed rail l, the switch pointswill be unlocked,and the points will therefore be forced open by the wheels in exactlythe same manner as would be the case if no point lock' were provided.

When the train which is trailing the switch has completely passed theswitch; the movable rails will return to their normal positions underthe bias of the spring connecting rod C. During this return movement ofthe movable rails there will be no deflection of these rails, and. the1ocking plunger 2le will be moved into engagement with the lock rod Lbefore the movable rails have reached their full normal positions inwhich the lock rod is in the proper position for the notches 32 thereinto receive the locking plunger 2'le. The springs 2171. will thereforebecome compressed, and will urge the locking plunger 2l'e intoengagement with the side of the lock rod, until the notches 32 move intoalignment with the locking plunger, at which time the energy stored inthe compressed springs Z'In will force the locking plunger into place inthe notches, thus'restoring the switch to its normal locked condition.If the notches 32 in the lock rod L should not come into alignment withthe locking plunger, a suitable indication of this fact will be given bymeans of the circuit controller E referred to hereinbefore.

During a facing point move there is no lateral thrust on the movablerails corresponding to, or

commensurate with, that which occurs during a trailing movement, andwhat lateral thrust there is will be in the direction to permit thesprings 2111, to force the locking plunger further into the notches 32in the lock rod L.

With the apparatus constructed in the manner thus far described it mightpossibly happen that when a train passes over the switch in a facingpoint direction a piece of dragging equipment would hook onto the tierod 8 or the connecting rod 55, and would thus bend these parts out ofshape to thereby actuate the linkage which connects the tie rod 8 withthe locking device2l to cause the locking plunger 216 to becomewithdrawn from the notches 32 in the lock rod L and thus unlock theswitch. In order to prevent the possibility of such a condition fromoccurring I provide auxiliary electric lock mechanism which is efiectivewhen deenergized to lock the looking device 21 in the position in whichit is shown in the drawings.

As here shown, this auxiliary locking mechanism comprises a locking dog55 which is pivotally attached at its upper end to one end of a lever6|, and which cooperates .at its lower end with a notch 62 provided inthe upper side of an extension 63 formed on the end member 21d of thelocking device 21. The lower end of the dog 60 also cooperates with twoother notches 64 and 65 which are formed in the frame 4| on oppositesides of the notch 62, and which align later-ally with the notch 62 whenthe locking device 21 occupies its locking position in which the lockingplunger 27c is within the notches 32 in the lock rod L, but not when thelocking device 2! is moved to its unlocking position in which thelocking plunger 21a is withdrawn from the notches 32 in the lock rod L.

The extension 63 is slidably supported at its forward end within aguideway 48 formed in the hold-down member 40. w

The dog further cooperates with a depressor' 66 which is pivotallysupported on a pin I66 mounted in a pair of upstanding arms 61 providedon the frame 4|, and which extends at one end between upstanding armswhich are formed on the locking dog 60. The other end of the dog 60 isbifurcated,

depressor cooperates with a cam 68 formed on the extension 63 in suchmanner that when the locking device occupies its proper lockingposition, the dog will be prevented by the depressor from being raisedfar enough to withdraw it from the aligned notches 62, 64 and 65.

In order to permit the dog to be withdrawn when it is desired to unlockthe switch in the intended manner, the notch 62 is made longer than thewidth of the dog, and the parts are so proportioned that the end 66b ofthe dog which cooperates with the cam 68 will ride off of the cam beforethe dog moves into engagement with the left-hand end of the notch, aswill be made clear presently.

Formed on the depressor is a stop finger 66a which cooperates with astop 61a provided on the arm 61 to limit the position to which the dogis free to rotate when it rides off of the cam 68.

The lever 6| is pivotally attached intermediate its ends to a fulcrumblock 10 which is mounted for vertical sliding movement within aguideway II provided in a cross member 12 formed on the frame M. Theportion of the block which extends through the guideway H is round, andin order to prevent it from turning and still permit the desiredvertical movement of the block, the block is pierced by a cotter key 13the ends of which extend with clearance into vertical slots 14 providedin the opposite side walls of the guideway.

The fulcrum block 10 normally occupies a lowermost position in which itis shown in Fig. 3, and in which its lower end rests on the upper sideof the cross member 2111 of the locking device 21, but is arranged to beforced upwardly to a raised position in which it rides on top of theextension 63 at one side of the cam 68 when the locking device 21 ismoved away from its locking position, and in order to facilitate movingthe fulcrum block to its raised position in response to the movement ofthe locking device to its unlocking position, the fulcrum block and theextension are provided with inclined surfaces 100. and 63a,respectively.

The end of the lever 6| opposite to the locking and is operativelyconnected with the armature 15 of an electromagnet M by means of pins 16which are secured to the sides of the armature at diametrically oppositepoints, and which extend with clearance into aligned vertical slots 11provided in the ends of the bifurcations. The armature I5 is biased bymeans of a spring member 18 to a released position, and the parts are soproportioned that when the dog 60 is within the notches 62, 64 and 65and the fulcrum block I0 is resting on top of the end member 21d, thearmature will be free to'move, by virtue of the slots TI, between itsreleased and attracted positions without causing movement of the lever6|.

The magnet M is secured at its lower end to the frame M, and is adaptedto be energized when a train trails the switch by track circuits ortheir equivalent associated with the switch. These track circuits formno part of my present invention and are therefore not shown in thedrawings. These track circuits may, for example, be similar to the trackcircuits shown 1n Letters Patent of the United States No. 1,606,455,granted to Frederick C, Stuart on November 9, 1926, in which event themagnet M may be controlled in the same manner as the magnet 38 shown inFig. 8 of said patent. V

Attached to the armature is an insulating strip 19 provided on itsunderside with a metal contact member which, when the armature moves toits lowermost position, bridges two contact fingers 8| and 82 to form acontact 80-8l82. The contact fingers 80 and 8| are secured at the endsopposite to the bridging member 80 to an insulating block 83 provided onthe frame 41. The contact 808l82 may be used to control a signal locatedat the switch, or for any other desired purpose.

The locking member further comprises a fiat spring 84 which is securedto the lever 6| adjacent to the locking plunger 60, and which isprovided at its free end with a return bend 84a, the

position in which it is shown in Fig. 1, and islocked in this positionby the locking device 21, and the magnet M is deenergized, as will bethe case if no train is then approaching the switch in either direction,or if a train is approaching the switch or passing over the switch in afacing point direction, the lever 6| will rotate by gravity to theposition in which the dog 60 enters the aligned notches 62, 64 and 65.As was pointed out hereinbeiore, when the dog is within the notches 62,64 and. 65, the locking device 2'! is prevented from moving to the rightfar enough to unlock the switch, and it will be seen, therefore, thatthe auxiliary locking mechanism provides a means for preventing theswitch from becoming unlocked under these conditions for any reason,due, for example, to dragging equipment hooking onto the lock releasinglinkage. It will also be seen that, when the switch is locked in itsnormal position by the locking device 21, and the magnet M isdeenergized, if the lever 6| should fail to rotate due to its gravitybias to the position in which the dog 6| enters the notches 62, 64 and65, the cam 68 will engage the depressor 66 and will rotate it to aposition in which it will force the dog downwardly to its properposition. Furthermore, if when the dog is within the notches 62, 64 and65, the locking plunger 21 should be moved in the direction to unlockthe switch far enough to raise fulcrum block 16, the dog will thenremain in the notches 62, 64 and 65 due to its gravity bias.

When the parts are in the positions in which they are shown in thedrawings and a train trails the switch, the resultant movement of thelock releasing linkage which takes place due to the lateral movement ofthe rails by the wheels of the train will cause the fulcrum block 10 tobe raised and will also cause the depressor to ride off of the cam 68.When this happens, if magnet M is energized, as will normally be thecase, the raising of the fulcrum block will rotate the lever 6| in aclockwise direction to a position in which the dog 60 is clear of thenotches. The motion of the locking device 21 necessary to force themechanism were not provided.

It should be noted that when magnet M becomes energized due to a traintrailing the switch, the contact 808l-82 will become closed, and willthus provide a means for controlling a suitable signal at the switch.This signal will usually be so controlled that it will only be clearwhen the contact 8ll 8l8'2 is closed, and the locking plunger 21c aschecked by the indication circuit controller E is in its proper lockingposition.

When it is desired 'to operate the switch by means of the hand-throwlever, the initial movement of the hand-throw lever will cause the pin85 to engage the return bend 84a of the spring 84 and bend the springupwardly until the looking device has been moved to the right far enoughto cause the cam 68 to move out of engagement with the depressor 66,whereupon the energy stored in the spring 84 will rotate the lever 6| toa position in which the dog 60 is withdrawn, the notches 62, 64 and 65thereby releasing the locking device. As soon as the locking device hasbecome released, the apparatus will then function in the mannerdescribed hereinbefore.

Although I have herein shown and described only one form of railwayswitch operating apparatus embodying my invention, it is understood thatvarious changes and modifications may be made therein within the scopeof the appended claims without departing from the spirit and scope of myinvention.

Having thus described my invention, what I claim is:

1. Switch operating mechanism comprising a reciprocable motion plate,means including a manually operable segment gear for reciprocating saidmotion plate, a locking plunger operably connected with said motionplate by means of springs and moved by said motion plate between twoextreme positions corresponding to the extreme positions of said motionplate, auxiliary means for at times moving said locking plunger awayfrom its one extreme position in opposition to the bias of said springs,said plunger being adapted when in its one extreme position to cooperatewith means for locking the switch in its one extreme position, meansactuated by said motion plate for moving the switch between its twoextreme positions, a member secured to said locking plunger and providedwith a notch and with a cam surface, a fulcrum block cooperating withsaid member and movable from a lowered to a raised position in responseto movement of said plunger away from said one position, anelectromagnet, 'a lever pivotally connected intermediate its ends tosaid fulcrum block and operatively connected at one end with thearmature of said electromagnet, a locking dog pivotally connected to theother end of said lever and movable when said fulcrum block occupies itslowered position and said magnet is deenergized to a locking position inwhich it enters the notch in said member to prevent movement of saidplunger to its other extreme position, a pivoted depressor cooperatingat one end with said dog and at the other end with said cam andeffective when said plunger occupies its one extreme position to forcesaid dog into said notch, the parts being so proportioned that movementof said fulcrum block to its raised position when said magnet isenergized will withdraw said dog from said notch, and means secured tosaid lever and cooperating with means secured to said segment gear formoving said lever to a position in which said dog is withdrawn from saidnotch when said gear is actuated in the direction to move said motionplate to its other extreme position.

v 2. The combination with-a railway switch movable-between normal andreverse positions and operating mechanism for said switch comprising amanually operable lever, means controlled byv said lever for operatingsaid switch, and alocking plunger which is biased to a locking positionwhen said switch is moved by said lever to its normal position and ismoved to an unlocking position prior to any movement of the switch whensaid lever is operated to move said switch away from its normal positionand which plunger cooperatesin its locking position with means forlocking the switch in its normal position, of a member secured to saidlocking plunger and provided with a notch, a locking dog movable to alocking position in which it enters said notch when and only when saidlocking plunger occupies its locking position and biased by gravity toits loclclng position and effective when in its locking position toprevent movement of said locking plunger away from its locking position,an electromagnet, means responsive to an initial movement of saidlocking plunger toward its unlocking position when said electromagnet isenergized for moving said locking dog to its unlocking position, andother means responsive to movement of said manually operable lever inthe direction to move said switch toits reverse position for moving saidlocking dog to its unlocking position.

3. The combination with a railway switch movable between normal andreverse positions and operating mechanism for said switch comprising amanually operable lever, means controlled by said lever for operatingsaid switch, and a locking plunger which is biased to a looking positionwhen said switch is moved by said lever to its normal position and ismoved to an unlocking position prior to any movement of the switch whensaid lever is operated to move said switch away from its normal positionand which plunger cooperates in its locking position with means forlocking the switch in its normal position, of a member secured to saidlocking plunger and provided with a notch and with a cam surface, afulcrum block cooperating with said member and movable from a lowered toa raised position in response to movement of said plunger away from itslocking position, an electromagnet, a second lever pivotally connectedintermediate its ends to said fulcrum. block and operatively connectedat one end with the armature of said electromagnet, a locking dogpivotally connected to the other end of said second lever and movablewhen said fulcrum block occupies its lowered position and said magnet isdeenergized to a locking position in which it enters the notch in saidmember to prevent movement of said plunger to its unlocking position, apivoted depressor cooperating at one end with said dog and at the otherend with said cam and efifective when said plunger occupies its lockingposition to force said dog into said notch, the parts being soproportioned that movement of said fulcrum block to its raised positionwhen said magnet is energized will withdraw said dog from said notch,and means secured to said second lever and cooperating with meansoperated by said manually operable lever for moving said second lever toa position in which said dog is withdrawn from said notch when saidmanually operable lever is actuated 1 in the direction to move saidswitch to its reverse position.

4. The combination with a spring switch, a

ing position, an electromagnet, and means controlled in part by saidelectromagnet and effective if and only if said electromagnet isenergized' for moving said locking dog to its unlocking position inresponse to an initial movement of said locking plunger toward itsunlocking position to permit movement of said locking plunger to itsfull unlocking position by said train actuated means. v

HERBERT L. BONE.

